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Discussion Starter #1
wanna get the big mutha thumpr cam (for nice lope and idle not so much for power) but it says i need a 9.5:1 compression ratio. anybody know what the stock ratio is on a 4.8 v8 13 silverado? and is it really neccessary to get to a 9.5:1?
 

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I would pick a cam more appropriate to your build, that will give a better lope than that cam.
 

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http://bit.ly/1r1tef1

Never heard of compression ratio being an issue. Sounds like you need to read much more about cams/supporting mods in LS engines.
 

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want lope? go find a 212/218 108lsa
 

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Discussion Starter #8
Do you only want it for the sound of a cam?
i mainly want it to sound nice and lope nice at idle and sound aggressive on heavy acceleration but i do want some power to come from it since i hav to spend alot of money on supporting mods and the cam itself. im not lookin for just all power if that makes sense. cuz i meen its a daily driver
 

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Discussion Starter #9
Cam timing plays a role in the engine's dynamic compression. A lot of overlap and low static compression will give poor low speed performance.

4.8 static comp is 8.8:1, so my advice is pick a different cam.
so not changing your CR isnt going to like blow the engine or anything is it?
 

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This is gonna be good
 

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so not changing your CR isnt going to like blow the engine or anything is it?
lol

Its not like you can just pick up a screwdriver and change your CR.
 

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that is a horrible cam for your little 4.8
you can make a 212-218 lope pretty good with someone that knows how to tune.
I wouldn't worry about that cam and stock compression, I would just worry about using that cam
 

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lol

Its not like you can just pick up a screwdriver and change your CR.
You mean I cant just get a tune that adds more compression? LOL
 

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Discussion Starter #20
that is a horrible cam for your little 4.8
you can make a 212-218 lope pretty good with someone that knows how to tune.
I wouldn't worry about that cam and stock compression, I would just worry about using that cam
thank you for the good info...and not the sarcastic responses like other ppl. i thought the whole point in forums was to help others. prolly gonna look into a 212-218 and then tune it with black bear
 
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